tl;dr - worked fine for me, but the building was pretty anti-airbnb, and it's a bit far from Bangkok proper.
I booked this place because I wound up with an unexpected week in Bangkok, and I wanted a good place to work from. I planned to do very little sightseeing, so the fact that this place was ~40mins from downtown Bangkok was totally fine with me.
The good - the apartment itself was great. A bit small, but totally fine for one person. I didn't do much cooking (why would you? eat street food!) but it seemed like it had all the utensils. The pool is also really nice, and the gym was just what I needed! There's a 24-hour convenience store on the ground floor, and a pricey-but-good coffee place as well.
The bad - there are some really big "NO AIRBNB" signs right when you walk into the lobby, and it just sets up a weird dynamic with the people that live there full time, where you feel like they don't want you there. Same for the staff - awkward elevator rides, some comments, etc. I wouldn't have minded this so much, but it would have been nice to know what I was getting into - so hopefully, this review helps you there!
Also, there's not a lot of good food *right* outside the apartment, you've got to walk ~10 mins (in either direction) to find the good stuff. Worth it, though!
So all in, I had a pretty good stay at Sunny's place (never met them, seemed like a company) - other than weird vibes from the other building residents, and some loooong BTS rides on the few occasions I needed to go to Bangkok proper.